• Journal of the Korean Ceramic Society
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• v.45 no.6
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• pp.336-344
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• 2008

Rheological properties of cement pastes containing blast furnace slag (BFS: 3,900, $7,910\;cm^2/g$) or fly ash powder (FA: 4,120, $8,100\;cm^2/g$) according to the ratio of water/binder (W/B) and the dosage of polycarboxylate type superplasticizer (PC) were investigated by a mini slump and a coaxial cylinder viscometer. In this experiment, the ratio of replacing OPC with BFS or FA was 30 wt%, the W/B was from 30 to 70 wt%. As a result, the fluidity of cement paste containing BFS or FA was improved with increasing W/B and the dosage of PC. BFS or FA replaced cement paste with W/B 70% and PC 0.3% showed the highest fluidity. The segregation range of cement paste was occurred below $10\;d/cm^2$ of the yield stress and below 50 cPs of the plastic viscosity by the coaxial cylinder viscometer. And also it was formed that the plastic viscosity and the yield stress of FA replaced cement paste were higher than them of BFS replaced cement paste.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.32-33
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• 2015

Depending on the industrialization, construction market has grown buildings are based on concrete will continue to increase. But the problems of environmental pollution come to the fore with the indiscriminate use of concrete and rapid development. In addition, carbon dioxide(CO₂) in the process of producing cement being emitted a large amount of has been caused a serious problem of environmental pollution. This trend is being actively conducted research to reduce the use of cement. In this study, eco-friendly materials, such as flats, Blast-furnace slag by mix and cement review the mechanical characteristics of the mudflats eco-friendly cement mortar to reduce the usability of the review were seen as a green building material.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.72-77
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• 1995

Blast-furnace slag cement has been used widely as a structural material due to the latent hydraulicity of granulated ground blast furnace slag(GGBS)for a long time as The wall as ordinary portland cement. In this study, based on the fundamental investigation on the high strength and high durable concrete using the high fineness GGBS the following remarks can be made. 1) The average desired strenth of concrete is Or=600~800kg/$\textrm{cm}^2$. 2) The above high strength concrete using the high fineness GGBS is more workable than those using only OPC. 3) The adiabatic temperature and drying shringkage decrease, so the density and resistance to sea water attack increase as results. 4)The unit cement content and unit air entrained admixture at the same desired strength of concrete decrease, so the economical high strength concrete can be manufactured from using the high fineness GGBS.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.64-69
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• 1999

Slags are by-products of the metallurgical industry. The most important slag from the standpoint of the quantity used as building material is iron blastfurnace slag. Slags are either crystalline stable solid used as aggregates or glassy material used as hydraulic binder. Slag cements are low heat of hydration cements. Slags react more slowly with than portland cement but they can be activated chemically. Activatiors can be either alkaline activators such as soda, lime, sodium carbonate, sodium silicate or sulphate activators such as calcium sulphate or phosphogypsum. So, in this study slaked lime was used as an activator that the compressive strength of this modified cement(M1 type) is high range in early age. And initial setting time of M1 type cement was shorter than conventional cements.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.205-210
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• 2000

This study concerns the cement-solidification. stabilization of the electric furnace dust. Compressive strength and leaching test of heavy metals were evaluated for varing types and ratios of cements and the effect of some additives of hauyne clinker and slag were also discussed. In this cases of using cement binders more than 30%, the compressive strength showed the values over 150kgf/cm2. so it can be used as filler for concrete precastings. Type III cement and Hauyne clinker improved the compressive strength, especially early strength. Leaching amount of heavy metals was decreased when using type III cement and adding hauyne clinker and slag. The values were especially low in the case of slag addition.

• Journal of the Korean Ceramic Society
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• v.37 no.2
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• pp.145-151
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• 2000

In order to investigate the rheological properties of belite-rich cement(BRC) added polycarbonate-based superplasticizer and blastfurnace slags which have different blaines at 4500, 6000 and 8000$\textrm{cm}^2$/g, the change of minislumps and mortar slumps are measured with time. The rheological properties improve as specific surface area of added slag decreases or amount of polycarbonate-based superplasticizer increases. The slump loss can be controlled effectively by the steric hinderance effect of polycarbonate-based superplasticizer. According to the results, when mix proportion of the mortar is 1.5% mass content of superplasticizer and 30% mass addition of blastfurnace slag which blaine is 4500$\textrm{cm}^2$/g, the best mortar slump can be achieved without any significant segregation of materials.

• Journal of the Korean Ceramic Society
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• v.32 no.8
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• pp.873-880
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• 1995

In order to prepare the modified belite (C2S-C4A3S-C4AF-CS) cement with low energy, clinkers were synthesized by converter slag, limestone, gypsum and clay. The synthesized clinkers were characterized and the hydration processes were investigated by XRD, SEM and microconduction calorimetry. The hydrates were mainly C-S-H and ettringite. The needle-like ettringite formed by the hydration of C4A3S at the early stage of hydration was filled in the inner vacant spaces of the hardened body and it might contribute to the rapid-hardening phenomena. The hardened body became stronger due to the hydration of C2S at the later period. The compressive strengths of the cement-3 mortars hydrated for 3, 7 and 28 days were 115, 128 and 211 Kgf/$\textrm{cm}^2$, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.130-131
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• 2016

In this study, moisture absorption coefficient and efflorescence properties of Ordinary Portland cement and alkali-activated slag cement mortar were assessed according to their red mud substitution ratio. Tests were conducted to determine the cause of efflorescence, which is a significant obstacle to the recycling of red mud as a sodium activator in alkali-activated slag cement, and to find a method to control efflorescence.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.161-162
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• 2017

As the use of cement increases with the development of modern society along with the increase of buildings, environmental pollution intensifies and researches on industrial byproducts are continuing. Research on blast furnace slag and fly ash as industrial byproducts is increasing, and research on industrial byproducts such as polysilicon sludge and paper ash used in this study is increasing. Blast furnace slag, which is one of the industrial byproducts, has been widely studied as a material used with cement. However, in this study, we fabricated lightweight matrix of polysilicon sludge and paper ash replaced based on blast furnace slag, and performed SEM analysis.

• Cement Symposium
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• no.28
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• pp.47-53
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• 2001